In all the speculation about what the Democratic "Plan B" could be (should President Joe Biden decide not to continue his run for re-election), so far there are really only two basic scenarios: an open convention, with multiple candidates vying for the nomination; or, conversely, Biden anointing Vice President Kamala Harris to stand in for him. But there are now two interesting developments which could be an indication of some possible party unity on the horizon. This is only a mere possibility right now -- it is in no way guaranteed -- but if it happened, it might be the best option possible for the Democratic Party.

The first development was that Michigan's Governor Gretchen Whitmer was directly asked in a recent interview if she would consider running for the presidential nomination, if Joe Biden stepped down. Her answer was an unequivocal: "No." The second development came when California's Governor Gavin Newsom was asked about a previous commitment he had made last year; that he would not run against his fellow Californian Kamala Harris for the presidency. When asked if Newsom still felt that way, he responded: "Of course, yes."

Now, politicians routinely insist that they won't run... right up until they do. Then they have some breezy justification for why things have changed, and everyone forgets all about it. On the Republican side in this election cycle, we saw Nikki Haley do this -- initially she swore she would never directly challenge Donald Trump for the Republican nomination, but then she reconsidered and threw her hat in the ring anyway. Few mentioned it beyond that point, because it is such a common flip-flop for a politician to make. So perhaps we should take the promises of Whitmer and Newsom right now with a grain of salt.

It is interesting, however, to take them at face value. Newsom and Whitmer were two of the biggest names being speculated about, should Biden decide to step down. There are others as well -- the governors of Illinois, Kentucky, Pennsylvania, and Maryland just to name a few, as well as some other Democrats who harbor presidential ambitions. But most of them (with a few notable exceptions such as Pete Buttigieg) don't already have a national political presence. Newsom and Whitmer already do, to some extent. With them out of the running, the chances of Harris winning an open convention go up. If more of the people being speculated about now follow the lead of Newsom and Whitmer, it could go a long way towards clearing the field for Harris.

Part of the fears some Democrats have of what would happen in a Plan B scenario are that the infighting would be bad for the party and bad for whomever emerged as the nominee. It would weaken them and possibly leave factions of the party so disappointed that they wouldn't support the nominee, to put this slightly differently. But if Plan B was defined -- even before Biden had to make his big decision -- as: "Kamala Harris will be the nominee, no matter what," then it might just make that decision a little easier for him to make.

Harris might not be the first choice of every Democrat, or even of every Democratic delegate to the national convention (the people who actually will select the party's nominee). Many would prefer to back a different candidate, for various reasons. But Harris is already building up a very strong argument for the party to unify behind her, without even lifting a finger: her recent polling is better than Biden's. She might well be able to beat Trump easier than Joe could. And this could even grow, as the speculation swirls about Biden possibly dropping out. Previous to the debate, nobody had really given the question a whole lot of thought. But since then, people are indeed thinking about who might best carry the torch forward if Biden were to pass it. And so far, Harris has emerged as an entirely-acceptable choice.

She wouldn't be a shoo-in, of course. She's not trouncing Trump in the polls. She does a few points better than him, that's all. But Biden does a few points worse, and even though that's not much of a shift, it might be enough.

Now add to all this what could happen if more and more possible candidates followed the lead of Whitmer and Newsom. If more and more of these prominent Democrats issued unequivocal statements that they would not challenge Harris, then the public would begin to see her as the only real possible replacement for Biden. It would be interesting to see what the polling had to say if that happened, that's for sure. Would more and more voters rally around her? Would her numbers go up against Trump? If Democratic voters knew for a fact that there wouldn't be a big convention fight, would that be more of a reason for them to support Harris?

Harris could generate a lot more enthusiasm for herself if she saw a clear field in front of her. She could excite the electorate in a way Biden just can't, to put it another way. And she could do all this while still remaining loyal to Biden and not saying a word about him leaving the race until it happened (which she would have to do -- she'd have to show unflinching loyalty to Biden until he independently made up his own mind).

If Democrats knew that they could avoid a big huge contentious floor fight for the presidential nomination, that would probably come as a real relief to many of them. Again, Kamala Harris might not have been everyone's first choice to replace President Joe Biden, but she already has the strongest vote of confidence imaginable -- because she already was Biden's first choice of a successor. She was chosen from a multitude to be his running mate. Biden has always shown Harris the same loyalty she shows him. Biden was vice president, so he knows full well the ins and outs of the dynamic between the veep and the president.

Joe Biden getting to anoint his heir apparent -- after already choosing her to take over from him during his first term and refusing to replace her on the ticket for his second -- would hopefully ease the sting of ending his campaign. So it will be interesting in the next few days to see if enterprising journalists start asking the same question to other Democrats who have been mentioned as possible Biden replacements, and it will also be interesting to hear what they say in response. If the "I won't challenge Harris" movement begins to spread widely, it certainly would clarify the whole Plan B idea for everyone, that's for sure.

-- Chris Weigant

Follow Chris on Twitter: @ChrisWeigant